CATAGORIES OF PROGRAMS

    Click on the category to see the listed programs.

    Analytic Element

    Geostatistics

    Salt Water Intrusion

    Unsaturated Transport (Analytical)

    Bioremediation

    Heat Transport

    Saturated Flow
    (Analytical)

    Unsaturated Transport (Numerical)

    Capture Zone

    Hydrogeochemistry

    Saturated Flow
    (Numerical)

    User Interface

    Data Managers

    Manage/Optimization

    Saturated Transport (Analytical)

    Utilities

    Education/Test Sets

    Multi-Phase Flow

    Saturated Transport (Numerical)

    Vapor Transport

    Fractured Media

    Parameter Estimation

    Unsaturated Flow

    Virus Transport

     

    MODPATH and MODPATH-PLOT form a particle tracking post-processing package which was developed to compute three-dimensional path lines based on output from steady-state and transient simulations obtained with the U.S. Geological Survey modular three-dimensional finite-difference ground-water flow model MODFLOW.

    Analytic Element

    CZAEM

    A single-layer model for simulating steady flow in homogeneous aquifers using the Analytic Element Method (Freeware).

    GFLOW

    A Windows program based on the analytic element method of steady state flow in a single heterogeneous aquifer using the Dupuit-Forchheimer assumption (Educational version is free) .

    GMS

    GMS supports both finite-difference and finite-element groundwater models in 2D and 3D including MODFLOW 2000, MODPATH, MT3DMS/RT3D, SEAM3D, FEMWATER, PEST, UTEXAS, MODAEM and SEEP2D.

    PhreFlow

    A program that models three dimensional unconfined transient groundwater flow and transport using the superposition of analytic functions (Freeware) .

    SLAEM/MLAEM

    The AEM family of computer programs, SLAEM, MLAEM/2, and MLAEM, are based on the Analytic Element Method and intended for modeling regional groundwater flow in systems of confined, unconfined, and leaky aquifers.

    Visual AEM

    A graphical user interface for single and multi-layer analytic element modeling of (mostly) steady-state groundwater flow and numerical/analytical modeling of vertically-averaged contaminant transport (Freeware) .
    Bioremediation

    BIOPLUMEIII

    Finite difference model for simulating the natural attenuation of organic contaminants in ground-water due to the processes of advection, dispersion, sorption, and biodegradation. Biotransformation processes are potentially important in the restoration of aquifers contaminated with organic pollutants. As a result, these processes require evaluation in remedial action planning studies associated with hydrocarbon contaminants.

    GMS

    A comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    BIOF&T

    BIOF&T models biodegradation, flow and transport in the saturated and unsaturated zones in two or three dimensions in heterogeneous, anisotropic porous media or fractured media. BIOF&T allows real world modeling not available in similar packages.

    Bioslurp

    BIOSLURP is an areal finite-element model to simulate three-phase (water, oil and gas) flow and multicomponent transport in ground water in the unsaturated zone gas phase.

    BioSVE

    BioSVE incorporates soil vapor extraction (SVE), vacuum enhanced recovery (bioventing) and biodegradation into one easy-to-use screening model. BioSVE is a user-friendly screeing tool which allows site evaluation with limited sampling events.

    Groundwater Vistas

    Groundwater Vistas (GV) is a sophisticated Windows graphical user interface for 3-D groundwater flow & transport modeling . GV couples a powerful model design system with comprehensive graphical analysis tools.

    Hydrogeochem

    HYDROGEOCHEM is a coupled model of hydrologic transport and geochemical reaction in saturated-unsaturated media. It is designed to simulate transient and/or steady-state transport of Na, aqueous components and transient and/or steady-state mass balance of Ns adsorbent components and ion-exchange sites.

    Hydrogeochem2

    HYDROGEOCHEM 2 is a modification of HYDROGEOCHEM which was designed to solve coupled hydrologic transport and geochemical equilibrium problems. The modification includes replacement of the EQMOD chemical equilibrium subroutines by a mixed chemical Kinetic and Equilibrium Model (KEMOD) to deal with species whose concentrations are controlled by either thermodynamics or kinetics.

    Processing MODFLOW Pro (PMWIN)

    Processing MODFLOW Pro (PMWIN) is a graphical interface for MODFLOW, MODPATH, PMPATH, MT3D, RT3D, MOC3D, PEST and UCODE
    Capture Zone

    AGU-10

    A collection of screening level analytical flow and transport programs for homogeneous, isotropic flow fields, based on the American Geophysical Union's Water Resources Monograph 10. It consists of five simulation programs in FORTRAN and two pre-/postprocessors in Microsoft BASIC. (Freeware) .

    CAPZONE

    CAPZONE is an analytical flow model that can be used to construct ground-water flow models of two-dimensional flow systems characterized by isotropic and homogeneous confined, leaky-confined, or unconfined flow conditions. CAPZONE computes drawdowns at the intersections of a regularly-spaced rectangular grid produced by up to 100 wells using either the Theis equation or the Hantush-Jacob equation. (Freeware)

    PAT

    PAT is an analytical model for the computation and graphical representation of pathlines and travel times of ground-water in an infinite or semi-infinite homogeneous and isotropic confined aquifer. The computed steady-state flow field can include arbitrary pumping and injection wells superimposed with a natural homogeneous regional flow which is consistent with the boundary chosen. (Freeware)

    TWODAN

    TWODAN, two-dimensional analytic flow modeling software from Fitts GeoSolutions, was just upgraded to a 32-bit Windows application (Version 5.0). This adds a simple and intuitive interface to TWODAN's advanced analytic modeling capabilities.

    WHAEM

    WhAEM 2000 is a public domain, ground-water flow model designed to facilitate capture zone delineation and protection area mapping in support of the State's Wellhead Protection Programs (WHPP) and Source Water Assessment Planning (SWAP) for public water supplies in the United States. Program operation and modeling practice is covered in a series of progressively more complex representations of the wellfield tapping a glacial outwash aquifer for the city of Vincennes, Indiana.

    WHPA

    The program 'WHPA' is a modular, semi-analytical ground-water flow model designed to assist State and local technical staff with Well-head Protection Area (WHPA) delineation. The model, developed for U.S. EPA, consists of 4 independent computational modules that may be used to delineate capture zones.

    ASM

    ASM (Aquifer Simulation Model) is a numerical model for two-dimensional horizontal or vertical simulation of ground-water flow and solute transport problems. The flow equation is solved using a node-centered finite difference method.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    FLOWPATH II

    FLOWPATH is a 2-D finite difference, steady-state ground-water flow model for calculation of wellhead protection zones, hydraulic heads, ground-water velocities, time related pathlines, capture zones, water balances and steady state drawdown distributions.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    GROUNDWATER VISTAS

    Groundwater Vistas (GV) is a unique groundwater modeling environment for Microsoft Windows that couples a powerful model design system with comprehensive graphical analysis tools. GV, developed by the author of ModelCadTM, is a model-independent graphical design system for MODFLOW and related models.

    MODPATH

    PATH3D

    PATH3D can be applied to help visualize three-dimensional flow fields, to delineate contaminant capture zones or wellhead protection zones, and to evaluate the effectiveness of groundwater remedial scenarios under complex hydrogeological conditions. PATH3D is a valuable extension to a groundwater flow model, and is frequently a practical alternative to a contaminant transport model.

    SWIFT

    SWIFT-98 is a fully transient, three-dimensional model which simulates the flow and transport of fluid, heat (energy), brine, and radionuclide chains in porous and fractured geologic media.

    Data Managers

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    GROUNDWATER VISTAS

    Groundwater Vistas (GV) is a unique groundwater modeling environment for Microsoft Windows that couples a powerful model design system with comprehensive graphical analysis tools. GV, developed by the author of ModelCadTM, is a model-independent graphical design system for MODFLOW and related models.

    Education/Test Sets

    MODFLOW: EPA PROBLEM SET

    This manual addresses the principles of ground-water flow modeling and the modeling options associated with MODFLOW and provides twenty problem sets that illustrate use of MODFLOW including principles, input/output, options, rules of thumb, and common modeling mistakes.

    PAJARO VALLEY - MODFLOW DATA SET

    Pajaro Valley is a simulation data set for use with the three-dimensional finite difference ground-water flow model MODFLOW by McDonald and Harbaugh (USGS, 1988). The data set represents a three-layer mathematical model of the Pajaro Valley Aquifer System, California, developed by Mitten and Londquist (USGS, 1990).

    RANDOM WALK (RW) PROBLEM SET

    This problems set features the random walk technique for studying solute transport problems in groundwater. It includes an analytical version of the Random Walk model and 8 problem sets demonstrating how the random walk technique works.

    Fractured Media

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    MODFLOW

    MODFLOW is often used for fractured flow simulations, even though only the HFB Package specifically addresses fractured flow simulation.

    NETFLO

    NETFLO is a model to simulate steady-state three-dimensional ground-water flow in a heterogeneous medium using an equivalent network of series and parallel flow members. Where the stratigraphy does not suggest a particular network configuration, a network may be specified along principal stream tubes specified with a more general three-dimensional ground-water flow code.

    POLLUTE

    The POLLUTEv7 software provides fast, accurate, and comprehensive contaminant migration analysis capabilities. This program implements a one and a half dimensional solution to the advection-dispersion equation.

    SWIFT

    SWIFT-98 is a fully transient, three-dimensional model which simulates the flow and transport of fluid, heat (energy), brine, and radionuclide chains in porous and fractured geologic media.

    TRAFRAP-WT

    TRAFRAP-WT (TRAnsport in FRActured Porous media with Water Table boundary conditions) is a two-dimensional finite element code designed to simulate ground-water flow and solute transport in fractured or granular aquifers, and is capable of treating both (leaky-)confined and water table systems. Fractured porous media are represented by either the discrete-fracture or dual porosity approaches, or a combination of both.

    VERTPAK-1

    VERTPAK-1 is a package of eight analytical solutions covering fluid flow, rock deformation and solute transport in fractured and unfractured porous media.

    Geostatistics

    COVAR

    COVAR is a program for generating two-dimensional fields of autocorrelated parameters which are normally or log-normally distributed (e.g., hydraulic conductivity). The program uses a technique based on (Choleski) matrix decomposition. The generated parameter field represents a major requirement in the stochastic analysis via Monte-Carlo techniques.

    GEO-EAS

    GEO-EAS (Geostatistical Environmental Assessment Software) is a collection of interactive software tools for performing two-dimensional geostatistical analyses of spatially distributed data. Programs are provided for data file management, data transformations, univariate statistics, variogram analysis, cross validation, kriging, contour mapping, post plots, and line/scatter graphs. (Freeware) .

    GEOPACK

    GEOPACK is a user-friendly geostatistical software system. It consists of a package of programs for conducting analyses of the spatial variability of one or more random functions. GEOPACK includes several statistical analysis options. Basic statistics which can be calculated include the mean, median, variance, standard deviation, skew, kurtosis, maximum value, and minimum value. Programs are also included for linear regression, polynomial regression, and the Kolomogorov-Smirov test for distribution, and for calculating various percentiles of a selected data set. (Freeware) .

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    MAP

    The Monitoring Analysis Package MAP has been developed as a tool for the design of monitoring networks. MAP consists of the Plume Generation Model PLUME, the Monitoring Efficiency Model MEMO, and the Contamination Probability Model COPRO.
    Heat Transport

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    HOTWTR

    The program 'HOTWTR' is a block-centered finite difference model for simulating three-dimensional steady-state groundwater flow and heat transport in an isotropic, heterogeneous confined aquifer system with uniform thermal properties and no change of state. The interblock transmissivities are calculated as the harmonic mean of the adjacent blocks.

    HST3D

    HST3D:A Computer Code for Simulation of Heat and Solute Transport in Three-Dimensional Ground-Water Flow Systems simulates ground-water flow and associated heat and solute transport in three dimensions (Freeware) .  

    HYDRUS 1D

    HYDRUS-1D is a Microsoft Windows-based modeling environment for analysis of water flow and solute transport in variably saturated porous media. An interactive graphics-based user interface HYDRUS-1D was developed in support of the HYDRUS computer model (Freeware) .

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    ICE-1

    ICE-1 is a research model for the analysis of coupled flow of water, heat and solute in unsaturated, partially frozen soils, including heave effects. The model is based on solving simultaneously equations representing the suction-water content relationship, the hydraulic conductivity function, equation of state for energy of the liquid phase, approximate time integral of Darcy's law, approximate time integral of the Fournier heat diffusion equation, and the mass balance of solutes.

    SEAWAT

    SEAWAT is a generic MODFLOW/MT3DMS-based computer program designed to simulate three-dimensional variable-density groundwater flow coupled with multi-species solute and heat transport. The program has been used for a wide variety of groundwater studies including those focused on brine migration in continental aquifers as well as those focused on saltwater intrusion in coastal aquifers.

    SUTRA

    SUTRA is a model for saturated-unsaturated, variable-density ground-water flow with solute or energy transport (Freeware) .

    Hydrogeochemistry

    MINTEQA2

    MINTEQA2 is a geochemical equilibrium speciation model for dilute aqueous systems. The model can be used to calculate the mass distribution between the dissolved, adsorbed, and multiple solid phases under a variety of conditions including a gas phase with constant partial pressure.

    MINTEQAK

    MINTEQAK is an extensive modification of the MINTEQA2 code to model the change in composition of aqueous flow as it traverses a wetland/reactor system. The code allows modeling of an anaerobic wetland/ reactor, an aerobic wetland, or an anaerobic wetland/ reactor in series with an aerobic wetland.

    NETPATH

    NETPATH is an interactive program for modeling net geochemical mass-balance reactions between an initial and final water along a hydrologic flow path. Alternatively, NETPATH computes the mixing proportion of two initial waters and net geochemical reactions that can account for the observed composition of a final water (Freeware) .

    PHREEQC

    PHREEQC is a computer program for speciation, reaction-path, advective transport, and inverse geochemical calculations. Designed to perform a wide variety of aqueous geochemical calculations (Freeware)

    PHREEQE

    PHREEQE is a geochemical reaction model which is based on an ion pairing aqueous model. PHREEQE can determine pH, redox potential, and mass transfer as a function of reaction progress, and also solution composition in equilibrium with multiple phases.

    PHRQPITZ

    PHRQPITZ is a computer program capable of making geochemical calculations in brines and other electrolyte solutions of high concentrations using the Pitzer virial-coefficient approach for activity-coefficient corrections.

    WATEQ4F

    WATEQ4F is a program for the calculation of chemical equilibrium in natural waters. It models the thermodynamic speciation of major and important minor inorganic ions and complex species in solution for a given water analysis and in situ measurements of temperature, pH, and redox potential.

    Manage/Optimization

    HYDRUS 1D

    HYDRUS-1D is a Microsoft Windows-based modeling environment for analysis of water flow and solute transport in variably saturated porous media. An interactive graphics-based user interface HYDRUS-1D was developed in support of the HYDRUS computer model (Freeware) .

    STANMOD

    STANMOD (STudio of ANalytical MODels) is a Windows based computer software package for evaluating solute transport in porous media using analytical solutions of the convection-dispersion solute transport equation (Freeware) .

    MAP

    The Monitoring Analysis Package MAP has been developed as a tool for the design of monitoring networks. MAP consists of the Plume Generation Model PLUME, the Monitoring Efficiency Model MEMO, and the Contamination Probability Model COPRO.

    OPTP

    OPTP is a simple, user-interactive DOS program for computing the optimal discharge of a well in terms of benefit (of water produced) versus pumping cost, using a single-variable (i.e., discharge) constrained nonlinear programming algorithm.

    Multi-Phase Flow

    NAPL

    NAPL Simulator conducts a simulation of the contamination of soils and aquifers which results from the release of organic liquids commonly referred to as Non-Aqueous Phase Liquids (NAPLS)

    Parameter Estimation

    CXTFIT

    Successful predictions of the fate and transport of solutes in the subsurface hinges on the availability of accurate transport parameters (Freeware) .

    PUMPTEST

    The PUMPTEST program package is a menu-driven set of independently run programs.

    SLUGC

    The program 'SLUGC ' is a graphic program for determining hydraulic conductivity values based on the analysis of slug tests using the Cooper, Bredehoeft and Papadopulos et al. method. The program simulates traditional manual curve fitting with an on-screen rendition of the graphical method, displaying the normalized Cooper et al. curves and the normalized field timedraw down data and subsequently moving the field data set using cursor keys to obtain the best fit.

    SLUGT2

    SLUGT2 is an updated version of program 'SLUGT' and computes hydraulic conductivity values based on the analysis of slug-test data.

    TGUESS

    TGUESS is a computer program for estimating transmissivity from specific capacity data. It calculates aquifer transmissivity using the Jacob equation and uses a correction for partial penetration as given by Sternburg (1973).

    THCVFIT

    THCVFIT is an interactive program to determine transmissivity and storage coefficient from pumping tests. The program is based on the nonsteady state Theis equation for radial flow using the Theis curve fitting method.

    THEISFIT

    THEISFIT uses a least squares procedure to obtain the "best" values for storage coefficient and transmissivity from experimental aquifer test data for an isotropic homogeneous nonleaky confined aquifer. It is based on an inverse formulation of the Theis equation solved using a least squares procedure.

    TIMELAG

    TIMELAG is a program to estimate hydraulic conductivity from single-well test. The method involves instantaneous raising or lowering of the water level in a well and measuring the water-level recovery through time.

    TSSLEAK

    TSSLEAK uses a least-squares fitting technique to calculate the "best" value for storage coefficient, transmissivity, leakage coefficient, and aquitard permeability from experimental pump test data as proposed by Hantush and Jacob.

    UN-GW

    The UN-GW software package consists of two parts: 1) data bases and utilities, and 2) mathematical models.

    VARQ

    VARQ is a program to calculate aquifer parameters by automatically fitting pump test data and the Theis type curve.

    WELL

    WELL is a computer program for analysis of tracer test data. It analyzes dispersion of a conservative solute introduced as a pulse in the recharge well of a two-well flow system using the general theory of longitudinal dispersion in nonuniform flow along streamlines.

    WELLTEST

    The WELLTEST program package consists of four independently marketed proprietary and public domain programs for the analysis of pump tests and slug tests.

    ASM

    ASM (Aquifer Simulation Model) is a numerical model for two-dimensional horizontal or vertical simulation of ground-water flow and solute transport problems. The flow equation is solved using a node-centered finite difference method.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    FTWORK

    The program 'FTWORK' is a block-centered finite difference model for simulating one-, two- and three-dimensional steady-state and transient flow and transient single species solute transport in saturated media under confined and unconfined conditions.

    INVFD

    INVFD is a two-dimensional, steady-state ground-water flow model, which can be used to estimate parameters by nonlinear regression. The model simulates (leaky) confined flow in a heterogeneous aquifer.

    MODFLOWP

    The WELLTEST program package consists of four independently marketed proprietary and public domain programs for the analysis of pump tests and slug tests (Freeware) .

    PEST2000

    PEST is a nonlinear parameter estimation package with a difference. The difference is that PEST can be used to estimate parameters for just about any existing computer model, whether or not a user has access to the model's source code.

    STANMOD

    STANMOD (STudio of ANalytical MODels) is a Windows based computer software package for evaluating solute transport in porous media using analytical solutions of the convection-dispersion solute transport equation (Freeware) .

    FP

    FP is a computer program for determining retention function parameters from experimental data. It is a historic model based an early formulation of the general retention function, relating the saturation to the capillary pressure in distributed soils.

    ONESTEP

    ONESTEP is a program for estimation of up to five unknown parameters in the van Genuchten soil hydraulic property model. The program require measurements of cumulative outflow with time during one-step outflow experiments.

    RETC

    RETC is a computer program which may be used to analyze the soil water retention and hydraulic conductivity functions of unsaturated soils. These hydraulic properties are key parameters in any quantitative description of water flow into and through the unsaturated zone of soils.

    SOHYP

    SOHYP is an analytical model for calculation of the unsaturated hydraulic conductivity function. The basis of SOHYP is a relatively simple equation for the soil moisture content-pressure head curve.

    SOIL

    SOIL estimates soil hydraulic properties using a nonlinear least-square analysis. Major input to the code includes pairs of measured water content and suction. The user can choose from the methods of Brooks and Corey (1964), Brutsaert (1966), Vauclin et al. (1979), and van Genuchten (1981) to estimate the soil-water characteristic function and the unsaturated hydraulic conductivity.
    Salt Water Intrusion

    CASE

    A package of five analytical models of the one-dimensional convective-dispersive transport equation with linear adsorption, zero-order production, and first-order decay.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    HST3D

    HST3D:A Computer Code for Simulation of Heat and Solute Transport in Three-Dimensional Ground-Water Flow Systems simulates ground-water flow and associated heat and solute transport in three dimensions (Freeware) .  

    MOCDENSE

    MOCDENSE is a two-dimensional, cross-sectional model for the analysis of saltwater intrusion. It simulates conservative solute transport and dispersion of one or two constituents in a ground-water system with density-dependent flow (Freeware) .  

    SEAWAT

    SEAWAT is a generic MODFLOW/MT3DMS-based computer program designed to simulate three-dimensional variable-density groundwater flow coupled with multi-species solute and heat transport. The program has been used for a wide variety of groundwater studies including those focused on brine migration in continental aquifers as well as those focused on saltwater intrusion in coastal aquifers.

    SHARP

    The program 'SHARP' is a quasi-three dimensional finite difference model for simulating freshwater and saltwater flow, separated by a sharp interface in layered coastal aquifers. The model accommodates multiple aquifers, separated by confining layers. The uppermost aquifer can be confined, semi-confined or unconfined with areally distributed recharge. Temporal variations in recharge and pumping are accounted for by introducing multiple pumping periods. The boundary conditions which can be modeled include prescribed flux boundaries, constant freshwater/and or saltwater head boundaries, mixed type boundary conditions. Aquifer properties can be both heterogeneous and anisotropic. The model can be used for both areal and cross-sectional studies.

    SUTRA

    SUTRA includes the SUTRA ground-water model and a number of utilities for pre- and post-processing for simulations in two or three spatial dimensions (2D or 3D) (Freeware) .

    SWICHA

    SWICHA is a three-dimensional finite element code for analyzing seawater intrusion in coastal aquifers. The model simulates variable density fluid flow and solute transport processes in fully-saturated porous media. It can solve the flow and transport equations independently or concurrently in the same computer run.

    SWIFT

    SWIFT-98 is a fully transient, three-dimensional model which simulates the flow and transport of fluid, heat (energy), brine, and radionuclide chains in porous and fractured geologic media.

    TARGET

    A simple, user-interactive DOS program for computing the optimal discharge of a well in terms of benefit (of water produced) versus pumping cost, using a single-variable (i.e., discharge) constrained nonlinear programming algorithm.

    Saturated Flow (Analytical)

    AGU-10

    A collection of screening level analytical flow and transport programs for homogeneous, isotropic flow fields, based on the American Geophysical Union's Water Resources Monograph 10. It consists of five simulation programs in FORTRAN and two pre-/postprocessors in Microsoft BASIC. (Freeware) .

    CAPZONE

    CAPZONE is an analytical flow model that can be used to construct ground-water flow models of two-dimensional flow systems characterized by isotropic and homogeneous confined, leaky-confined, or unconfined flow conditions. CAPZONE computes drawdowns at the intersections of a regularly-spaced rectangular grid produced by up to 100 wells using either the Theis equation or the Hantush-Jacob equation.

    GWFLOW

    The program 'GWFLOW' brings together seven frequently used analytical solutions for ground-water flow problems. It is a simple program for quick calculations.

    THWELLS

    THWELLS is an analytical model for calculating the drawdown or buildup of piezometric head due to the combined effect of up to up to 100 pumping and/or injection wells. The calculation of total drawdown is based on the Theis equation or Hantush-Jacob equation for non-steady state flow in an isotropic, homogeneous confined, leaky confined or unconfined aquifer of infinite extent.

    UN-GW

    The UN-GW software package consists of two parts: 1) data bases and utilities, and 2) mathematical models.

    VERTPAK-1

    A package of eight analytical solutions covering fluid flow, rock deformation and solute transport in fractured and unfractured porous media.

    WALTON35

    A series of 35 simple analytical and numerical models for flow, solute and heat transport and upconing of a fresh-salt water interface in saturated ground-water systems.

    WHPA

    The program 'WHPA' is a modular, semi-analytical ground-water flow model designed to assist State and local technical staff with Well-head Protection Area (WHPA) delineation. The model, developed for U.S. EPA, consists of 4 independent computational modules that may be used to delineate capture zones.

    Saturated Flow (Numerical)

    ASM

    ASM (Aquifer Simulation Model) is a numerical model for two-dimensional horizontal or vertical simulation of ground-water flow and solute transport problems. The flow equation is solved using a node-centered finite difference method.

    EIS/Biorem3D

    EIS/Biorem3D is a W95 automated environmental modeling platform that integrates data management (geographical, physical, and chemical), site characterization, grid design, simulation of flow, migration, visualization, and scriptable interactions of multiple chemical species of 12 interacting plumes of chemicals, nutrients, and daughter products in saturated 3D media.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    FLOWPATH II

    FLOWPATH is a 2-D finite difference, steady-state ground-water flow model for calculation of wellhead protection zones, hydraulic heads, ground-water velocities, time related pathlines, capture zones, water balances and steady state drawdown distributions.

    FTWORK

    The program 'FTWORK' is a block-centered finite difference model for simulating one-, two- and three-dimensional steady-state and transient flow and transient single species solute transport in saturated media under confined and unconfined conditions.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    GROUNDWATER VISTAS

    Groundwater Vistas (GV) is a unique groundwater modeling environment for Microsoft Windows that couples a powerful model design system with comprehensive graphical analysis tools. GV, developed by the author of ModelCadTM, is a model-independent graphical design system for MODFLOW and related models.

    HST2D/3D ENHANCED

    HST2D/3D is a finite difference computer model for the simulation of heat and solute transport in saturated porous media. The model is based on the original HST3D model developed by the USGS (Kipp, 1986), and is revised and extended by Verbeek Consultants for IF Technology in the Netherlands.

    HST3D

    HST3D:A Computer Code for Simulation of Heat and Solute Transport in Three-Dimensional Ground-Water Flow Systems simulates ground-water flow and associated heat and solute transport in three dimensions (Freeware) .  

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    INVFD

    INVFD is a two-dimensional, steady-state ground-water flow model, which can be used to estimate parameters by nonlinear regression. The model simulates (leaky) confined flow in a heterogeneous aquifer.

    JDB2D/3D

    JDB2D/3D consists of two fairly simple, easily modifiable computer programs for solving the two-dimensional, single-aquifer (JDB2D) and quasi-three-dimensional, multi-aquifer (JDB3D) formulation of the transient ground-water flow equation for confined and leaky-confined aquifer systems.

    MicroFEM

    Micro-Fem is an integrated large-capacity finite-element modeling system for steady-state and transient simulation of ground-water flow in multiple aquifer systems. The software supports iteractive mesh generation, input preparation, model computation, graphic postprocessing and plotting of results.

    MODFE

    MODFE is a modular 2D finite element model for simulation of steady-state or transient areal, cross-sectional, and axi-symmetric ground-water flow. Geometric and hydrologic aquifer characteristics in two spatial dimensions are represented by triangular finite elements and linear basis functions; 1D finite elements and linear basis functions represent time (Freeware) .

    MODFLOW96

    MODFLOW is a block-centered finite difference code for steady-state and transient simulation of two-dimensional, quasi-three-dimensional, and fully three-dimensional saturated, constant density flow problems in combinations of confined and unconfined aquifer-aquitard systems above an impermeable base (Freeware) .

    MODFLOWP

    The WELLTEST program package consists of four independently marketed proprietary and public domain programs for the analysis of pump tests and slug tests (Freeware) .

    MULAT

    MULAT is a program for the analysis of three-dimensional steady-state groundwater flow, and the advective transport of particles, including linear adsorption and desorption. The model assumes flow in the aquifer to be mainly horizontal, with vertical flow from one aquifer to another through the resistance layers.

    NETFLO

    NETFLO is a model to simulate steady-state three-dimensional ground-water flow in a heterogeneous medium using an equivalent network of series and parallel flow members. Where the stratigraphy does not suggest a particular network configuration, a network may be specified along principal stream tubes specified with a more general three-dimensional ground-water flow code.

    PLASM

    PLASM as distributed by the IGWMC is a programs package based on the Prickett Lonnquist Aquifer Simulation Program (PLASM) first published in 1971 by the Illinois State Water Survey. It consists of three finite-difference simulation programs and a preprocessor.

    PMWIN

    PM is graphical interface for simulation of threedimensional flow and solute transport problems. It supports the preparation of input files and analysis of simulation results for a range of MODFLOW-related programs including MODFLOW itself, the particle tracking programs MODPATH and PMPATH, the transport program MT3D, and the parameter estimation program PEST (Freeware) .

    RADFLOW

    RADFLOW is a menu-driven, user-interactive finite difference model for solving the horizontal radial time-varying flow equation in a confined, semi-confined or unconfined aquifer. The program calculates drawdowns resulting from a pumping well in the center of a circular homogeneous, isotropic aquifer subject to uniform areal recharge.

    SUTRA

    SUTRA includes the SUTRA ground-water model and a number of utilities for pre- and post-processing for simulations in two or three spatial dimensions (2D or 3D) (Freeware) .

    SWIFT-98

    SWIFT-98 is a fully transient, three-dimensional model which simulates the flow and transport of fluid, heat (energy), brine, and radionuclide chains in porous and fractured geologic media.

    TRAFRAP-WT

    TRAFRAP-WT (TRAnsport in FRActured Porous media with Water Table boundary conditions) is a two-dimensional finite element code designed to simulate ground-water flow and solute transport in fractured or granular aquifers, and is capable of treating both (leaky-)confined and water table systems.

    UN-GW

    The UN-GW software package consists of two parts: 1) data bases and utilities, and 2) mathematical models.

    VISUAL GROUNDWATER

    Provides interactive visualization capabilities for manipulating, rotating, and animating multiple three-dimensional data sets

    WALTON35

    A series of 35 simple analytical and numerical models for flow, solute and heat transport and upconing of a fresh-salt water interface in saturated ground-water systems.

    Saturated Transport (Analytical)

    3DADE

    3DADE is a Fortran computer program for evaluating a series of analytical solutions of the 3-Dimensional Advection-Dispersion Equation. The analytical solutions pertain to three-dimensional solute transport during steady unidirectional water flow in porous media with uniform transport and flow properties (Freeware)

    AGU-10

    A collection of screening level analytical flow and transport programs for homogeneous, isotropic flow fields, based on the American Geophysical Union's Water Resources Monograph 10. It consists of five simulation programs in FORTRAN and two pre-/postprocessors in Microsoft BASIC. (Freeware) .

    AT123D

    AT123D is based on an analytical solution for transient one-, two-, or three-dimensional transport of a dissolved chemical or radionuclide or heat in a homogeneous aquifer with uniform, stationary regional flow. The program assumes a stationary flow field parallel to the X-axis and allows for retardation (based on reversible instantaneous linear equilibrium sorption isotherm) and first-order decay.

    CXTFIT

    Successful predictions of the fate and transport of solutes in the subsurface hinges on the availability of accurate transport parameters (Freeware) .

    EPS-VHS

    EPA-VHS is a screening level model to predict maximum concentration of a pollutant at a prescribed distance downstream from a continuous source (at the compliance point). The model is based on an analytical solution for the transport of a conservative constituent in a homogeneous, isotropic aquifer with one-dimensional, horizontal, steady-state flow and dispersion perpendicular to the flow path.

    HPS

    HPS is an analytical model for simulating three-dimensional contaminant transport from a Horizontal Plane Source in a uniform regional ground water flow field. The model incorporates advective and dispersive (scale-dependent) transport, retardation, and first-order decay.

    MAP

    The Monitoring Analysis Package MAP has been developed as a tool for the design of monitoring networks. MAP consists of the Plume Generation Model PLUME, the Monitoring Efficiency Model MEMO, and the Contamination Probability Model COPRO.

    ONE-D

    ONE-D is a package of five analytical models of the one-dimensional convective-dispersive transport equation with linear adsorption, zero-order production, and first-order decay. The governing transport equations include terms accounting for convection, diffusion and dispersion.

    PLUME

    PLUME, also called PLUME-PH, is an analytical model for calculation of point concentration in a homogeneous aquifer resulting from a continuous, time-varying release of a single radioactive or non-radioactive component from a horizontal line source.

    PLUME 2D

    The program 'PLUME2D' is an analytical model based on closed-form solutions of the non-conservative solute transport equation for instantaneous and continuous releases of a tracer in one or more source locations as presented by Wilson and Miller (1978), and corrected by Wilson and Miller (1979).

    PRINCE

    PRINCE is a software package which contains ten analytical solute transport and flow models, widely known as the Princeton Analytical Models. The three flow models simulate two-dimensional groundwater flow in a confined homogeneous, isotropic aquifer of finite, semi-finite and infinite lateral extent.

    RWH

    RWH is an analytical version of the widely used RANDOM WALK flow and solute transport model, specifically designed for screening and educational purposes. It simulates solute transport from one or more sources in a homogeneous, isotropic, confined aquifer of constant thickness and infinite extent.

    RANDOM WALK

    The RANDOM WALK technique is outlined for studying mass transport problems dictated by analytical formula driven groundwater flow distributions. This is simpler than developing a finite-difference or finite-element flow model as input to a mass transport techniques.

    SOLUTE

    The program package "SOLUTE" is a set of five programs based on analytical solutions of the advective-dispersive transport equation for a non-conservative tracer solute.

    USGS-SOL

    USGS-SOL presents a series of analytical solutions of the partial differential equation describing the advective-dispersive transport of a non-conservative solute for a variety of boundary types and solute source configurations in one-, two-, and three-dimensions.

    VERTPAK-1

    A package of eight analytical solutions covering fluid flow, rock deformation and solute transport in fractured and unfractured porous media.

    WALTON35

    A series of 35 simple analytical and numerical models for flow, solute and heat transport and upconing of a fresh-salt water interface in saturated ground-water systems.

    Saturated Transport (Numerical)

    ASM

    ASM (Aquifer Simulation Model) is a numerical model for two-dimensional horizontal or vertical simulation of ground-water flow and solute transport problems. The flow equation is solved using a node-centered finite difference method.

    BIOPLUMEIII

    Finite difference model for simulating the natural attenuation of organic contaminants in ground-water due to the processes of advection, dispersion, sorption, and biodegradation. Biotransformation processes are potentially important in the restoration of aquifers contaminated with organic pollutants. As a result, these processes require evaluation in remedial action planning studies associated with hydrocarbon contaminants.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    FLOWPATH II

    FLOWPATH is a 2-D finite difference, steady-state ground-water flow model for calculation of wellhead protection zones, hydraulic heads, ground-water velocities, time related pathlines, capture zones, water balances and steady state drawdown distributions.

    FTWORK

    The program 'FTWORK' is a block-centered finite difference model for simulating one-, two- and three-dimensional steady-state and transient flow and transient single species solute transport in saturated media under confined and unconfined conditions.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    Groundwater Vistas

    Groundwater Vistas (GV) is a sophisticated Windows graphical user interface for 3-D groundwater flow & transport modeling . GV couples a powerful model design system with comprehensive graphical analysis tools.

    HST2D/3D ENHANCED

    HST2D/3D is a finite difference computer model for the simulation of heat and solute transport in saturated porous media. The model is based on the original HST3D model developed by the USGS (Kipp, 1986), and is revised and extended by Verbeek Consultants for IF Technology in the Netherlands.

    HST3D

    HST3D:A Computer Code for Simulation of Heat and Solute Transport in Three-Dimensional Ground-Water Flow Systems simulates ground-water flow and associated heat and solute transport in three dimensions (Freeware) .  

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    MIGRATE

    Using the MIGRATEv9 software, contaminant transport from multiple sources, either at the surface or buried, can be modeled quickly and accurately in two-dimensions.

    MOC

    A two-dimensional finite element code designed to simulate ground-water flow and solute transport in fractured or granular aquifers, and is capable of treating both (leaky-)confined and water table systems (Freeware) .

    MOC3D

    MOC3D is a 3D flow and transport model. The method of characteristics transport model is integrated with modflow and considers advection, dispersion, mixing from other fluid sources, linear sorption, and radioactive decay. Includes manual, source, executable and example files (Freeware) .

    MOCDENSE

    MOCDENSE is a two-dimensional, cross-sectional model for the analysis of saltwater intrusion. It simulates conservative solute transport and dispersion of one or two constituents in a ground-water system with density-dependent flow (Freeware) .

    MODFLOWT

    MODFLOWT is a new version of MODFLOW that includes modules for simulating three-dimensional transport. The new model, authored by Glenn Duffield of HydroSOLVE, solves equations for advective-dispersive transport with adsorption and first-order decay using a fully-implicit finite-difference technique developed for the public domain code FTWORK by GeoTrans, Inc (see elsewhere in this catalog).

    MT3DMS

    The modular three-dimensional transport model referred to as MT3D was originally developed by Zheng (1990) at S. S. Papadopulos & Associates, Inc., and subsequently documented for the Robert S. Kerr Environmental Research Laboratory of the United States Environmental Protection Agency.

    MULAT

    MULAT is a program for the analysis of three-dimensional steady-state groundwater flow, and the advective transport of particles, including linear adsorption and desorption. The model assumes flow in the aquifer to be mainly horizontal, with vertical flow from one aquifer to another through the resistance layers.

    PHREEQM-2D

    PHREEQM-2D is a multi-component mass transport model consisting of two coupled simulation programs: HST2D and PHREEQE. PHREEQE is a geochemical reaction model developed by the U.S. Geological Survey. PHREEQM-2D includes dissolution/precipitation and ion exchange, and supports kinetic computations for one mineral.

    PMWIN

    PM is graphical interface for simulation of threedimensional flow and solute transport problems. It supports the preparation of input files and analysis of simulation results for a range of MODFLOW-related programs including MODFLOW itself, the particle tracking programs MODPATH and PMPATH, the transport program MT3D, and the parameter estimation program PEST (Freeware) .

    POLLUTE

    The POLLUTEv7 software provides fast, accurate, and comprehensive contaminant migration analysis capabilities. This program implements a one and a half dimensional solution to the advection-dispersion equation.

    RAND3D

    The RAND3D program is a three-dimensional version of the random walk algorithm developed by Thomas Prickett at the Illinois State Water Survey as an efficient algorithm for solving ground water solute transport problems (Prickett, Naymik, and Lonnquist, 1981).

    SUTRA

    SUTRA includes the SUTRA ground-water model and a number of utilities for pre- and post-processing for simulations in two or three spatial dimensions (2D or 3D) (Freeware) .

    SWICHA

    SWICHA is a three-dimensional finite element code for analyzing seawater intrusion in coastal aquifers. The model simulates variable density fluid flow and solute transport processes in fully-saturated porous media. It can solve the flow and transport equations independently or concurrently in the same computer run.

    SWIFT-98

    SWIFT-98 is a fully transient, three-dimensional model which simulates the flow and transport of fluid, heat (energy), brine, and radionuclide chains in porous and fractured geologic media.

    TRAFRAP-WT

    TRAFRAP-WT (TRAnsport in FRActured Porous media with Water Table boundary conditions) is a two-dimensional finite element code designed to simulate ground-water flow and solute transport in fractured or granular aquifers, and is capable of treating both (leaky-)confined and water table systems. Fractured porous media are represented by either the discrete-fracture or dual porosity approaches, or a combination of both.

    VISUAL MODFLOW

    Unsaturated Flow

    INFIL

    INFIL is a numerical simulation model for solving the problem of ponded transient infiltration into a deep, homogeneous soil. The program is based on a four-term form of the Philip series solution (1957) of a one-dimensional form of the Richards equation.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    SWACROP

    SWACROP (Soil WAter and CROP production model) is a transient one-dimensional finite difference model for simulation of the unsaturated zone. It incorporates the process of water uptake by roots.

    UNSAT1

    UNSAT1 is a research model based on a generalized Hermetian finite element formulation for simulation of onedimensional flow in the unsaturated zone. This historic research code may be used to simulate moisture movement non-homogeneous soils with both abrupt layering and smoothly changing soil characteristics.
    Unsaturated Transport (Analytical)

    HELP

    The Hydrologic Evaluation of Landfill Performance (HELP) model was developed to help hazardous waste landfill designers and regulators evaluate the hydrologic performance of proposed landfill designs. The model accepts weather, soil and design data and uses solution techniques that account for the effects of surface storage, snowmelt, runoff, infiltration, evapotranspiration, vegetative growth, soil moisture storage, lateral subsurface drainage, leachate recirculation, unsaturated vertical drainage, and leakage through soil, geomembrane or composite liners.

    ICE-1

    ICE-1 is a research model for the analysis of coupled flow of water, heat and solute in unsaturated, partially frozen soils, including heave effects. The model is based on solving simultaneously equations representing the suction-water content relationship, the hydraulic conductivity function, equation of state for energy of the liquid phase, approximate time integral of Darcy's law, approximate time integral of the Fournier heat diffusion equation, and the mass balance of solutes.

    PESTAN

    The program PESTAN represents model for evaluating the one-dimensional vertical transport of organic pollutants through homogeneous soil to ground-water. It calculates organic movement based on a linear isotherm (S=K*C), first-order degradation, and longitudinal dispersion.

    RETC

    RETC is a computer program which may be used to analyze the soil water retention and hydraulic conductivity functions of unsaturated soils. These hydraulic properties are key parameters in any quantitative description of water flow into and through the unsaturated zone of soils.

    SUMMERS

    SUMMERS is a screening level interactive computer program for estimating soil cleanup levels. The model assumes that a percentage of rainfall at a polluted site will infiltrate and desorb contaminants from the soil based on equilibrium soil-water partitioning.
    Unsaturated Transport (Numerical)

    CHEMFLO

    CHEMFLO is a one-dimensional screening level model for simulation of the movement of water and chemicals in unsaturated soils. Water movement is described using Richards equation. The equation describing the movement of chemicals includes advective and dispersive transport, first-order decay in the liquid and solid phase, zero-order production or decay, and linear equilibrium adsorption (using a retardation coefficient.

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    HYD1D

    HYD1D is a Galerkin linear finite element program for simulation of transient 1D water flow, single-species solute transport, and heat movement in variably saturated porous media. The program solves the Richard's equation for flow, and convection-dispersion equations for both solute and heat transport.

    HYDRUS 1D

    HYDRUS-1D is a Microsoft Windows-based modeling environment for analysis of water flow and solute transport in variably saturated porous media. An interactive graphics-based user interface HYDRUS-1D was developed in support of the HYDRUS computer model (Freeware) .

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    MIGRATE

    Using the MIGRATEv9 software, contaminant transport from multiple sources, either at the surface or buried, can be modeled quickly and accurately in two-dimensions.

    POLLUTE

    The POLLUTEv7 software provides fast, accurate, and comprehensive contaminant migration analysis capabilities. This program implements a one and a half dimensional solution to the advection-dispersion equation.

    PRZM-2

    PRZM2 links two subordinate models in order to predict pesticide fate and transport through the crop root zone, and the unsaturated zone: PRZM and VADOFT. PRZM is a one-dimensional finite-difference model which accounts for pesticide fate and transport in the crop root zone.

    SESOIL

    SESOIL is a finite-difference soil compartment model designed for long-term hydrologic, sediment, and pollutant fate simulations. The model is designed to estimate pollutant concentrations in the soil following introduction via direct application at the surface and/or interaction with other media (i.e., deposition from air).

    SUMATRA-1

    SUMATRA-1 is a one-dimensional Hermitian finite element (HFE) model for simulation of simultaneous movement of water and a solute in a heterogeneous soil profile. The transport equation includes the effects of linear adsorption and zero- and first-order decay.

    SUTRA

    SUTRA includes the SUTRA ground-water model and a number of utilities for pre- and post-processing for simulations in two or three spatial dimensions (2D or 3D) (Freeware) .

    SWMS_2D

    SWMS_2D is a computer program for simulating water and solute movement in two-dimensional variably saturated media. The program numerically solves the Richards' equation for saturated-unsaturated water flow and the convection-dispersion equation for solute transport (Freeware) .

    VS2DI

    The VS2DI package contains all the tools that a user needs to create, run, and view results for a simulation of flow and transport through variably saturated porous media (Freeware) .

    User Interface

    FEFLOW

    FEFLOW is a professional software package for modeling fluid flow and transport of dissolved constituents and/or heat transport processes in the subsurface.

    GMS

    GMS is a comprehensive package which provides tools for every phase of a groundwater simulation including site characterization, model development, post-processing, calibration, and visualization. GMS is the only system which supports TINs, solids, borehole data, 2D & 3D geostatistics, and both finite element and finite difference models in 2D & 3D. Currently supported models include MODFLOW, MODPATH, MT3D, RT3D, FEMWATER, and SEEP2D.

    Groundwater Vistas

    Groundwater Vistas (GV) is a sophisticated Windows graphical user interface for 3-D groundwater flow & transport modeling . GV couples a powerful model design system with comprehensive graphical analysis tools.

    HYDRUS2D/3D

    A MS Windows Program for Simulating Water Flow and Solute Transport in Two and /Three-Dimensional Variably Saturated Media with full-color, high-resolution Graphics User Interface

    HYDRUS 1D

    HYDRUS-1D is a Microsoft Windows-based modeling environment for analysis of water flow and solute transport in variably saturated porous media. An interactive graphics-based user interface HYDRUS-1D was developed in support of the HYDRUS computer model (Freeware) .

    Utilities

    AQUACHEM

    AquaChem manages water quality data, allowing the user to plot data, perform common statistical analyses, model water chemistry with PHREEQC, and create simple reports.

    POCKET ESA

    This program has been designed to minimize the amount of time required to generate a Phase I ESA report and to maximize the flexibility of the final report. The data for the Phase I ESA can be collected on a Pocket PC or on a laptop.

    POCKET WINLOG

    Pocket WinLoG allows for quick and easy data collection in the field. You can use the stylus pen to enter any data into your logs or you can download your WinLoG templates to your Pocket PC for data entry in the field. Pocket WinLoG can store an unlimited number of templates previously designed in the WinLoG desktop version and pocket templates are represented on the menu tree form, displaying the types of data that can be entered for the log.

    TETRA

    TETRA estimates velocity components in three space dimensions from hydraulic head data. Groups of four observation points are connected to form tetrahedrons, and a linear interpolation is used to calculate head gradients for each tetrahedron.

    UNITS

    UNITS is a "Metric to Inch-Pound to Metric" conversion utility, which uses drop-down menus to select and process 12 categories and 75 different units of measure often used in ground-water hydrology.

    ZONEBUDGET

    ZONEBUDGET is a program that calculates subregional water budgets using results from the U.S. Geological Survey Modular Three-Dimensional Finite-Difference Ground-Water Flow Model (MODFLOW) (McDonald and Harbaugh, 1988).

    Vapor Transport

    PRZM-2

    PRZM2 links two subordinate models in order to predict pesticide fate and transport through the crop root zone, and the unsaturated zone: PRZM and VADOFT. PRZM is a one-dimensional finite-difference model which accounts for pesticide fate and transport in the crop root zone.

    Virus Transport  

    CANVAS

    CANVAS is a composite analytical-numerical code for simulation of transport and fate of viruses in ground-water. The code provides transient transport taking into account advection and dispersion of viral particles in the unsaturated and saturated zones, adsorption, inactivation (die-off), attachment and detachment kinetics and colloidal filtration.

    VIRALT

    VIRALT is a modular semi-analytical and numerical code that simulates the transport and fate of viruses in ground-water.

    VIRTUS

    VIRTUS (Viral Flow and Transport in the Unsaturated Zone) is a predictive finite difference model for virus fate and transport in unsaturated soil. The model allows the virus inactivation rate to vary based on soil temperature.